0807.9.8 Determine whether a chemical or physical change has occurred
By: Cheyenna Kemp
SCMS
vocabulary:
physical property- A characteristic that can be observed or measured without changing the identity of a substance.
chemical property- a characteristic that determines how a substance will interact with other substances during a chemical reaction.
reactivity- how likely the atoms or molecules of one substance are to form bonds with the atoms or molecules of other substances.
physical change- alters the physical properties of a substance without changing the identity of a substance.
chemical change- occurs when one substance changes into a new substance with different properties.
chemical reaction-the process by witch new substances form during a chemical change.
precipitate- a solid formed by a chemical reaction that takes place in a solution
combustion reaction- a chemical reaction in which oxygen combines with certain other substances,and heat and light are given off.
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A chemical change makes a substance that wasn't there before. There may be clues that a chemical reaction took place, such as light, heat, color change, gas production, odor, or sound. The starting and ending materials of a physical change are the same, even though they may look different.
Physical changes occur when objects undergo a change that does not change their chemical nature. A physical change involves a change in physical properties. Physical properties can be observed without changing the type of matter. Examples of physical properties include: texture, shape, size, color, odor, volume, mass, weight, and density
There are several differences between a physical and chemical change in matter or substances.
A physical change in a substance doesn't change what the substance is. In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.
For example, if a piece of paper is cut up into small pieces it still is paper. This would be a physical change in the shape and size of the paper. If the same piece of paper is burned, it is broken up into different substances that are not paper.
Physical changes can be reversed, chemical changes cannot be reversed with the substance changed back without extraordinary means, if at all. For example, a cup of water can be frozen when cooled and then can be returned to a liquid form when heated.
If one decided to mix sugar into water to make sugar water, this would be a physical change as the water could be left out to evaporate and the sugar crystals would remain. However, if one made a recipe for a cake with flour, water, sugar and other ingredients and baked them together, it would take extraordinary means to separate the various ingredients out to their original form.
When heat is given off in a chemical change or reaction, it is called an exothermic reaction. When heat is absorbed in a chemical change or reaction, it is called an endothermic reaction. The speed at which chemical reactions take place depend on the temperature pressure and how concentrated the substances involved in the chemical reaction are. Sometimes substances called catalysts are used to speed up or help along a chemical reaction. Light is helpful in the processing of film.
Fire indicates a chemical change.
Chemical changes take place on the molecular level. A chemical change produces a new substance. Examples of chemical changes include combustion (burning), cooking an egg, rusting of an iron pan, and mixing hydrochloric acid and sodium hydroxide to make salt and water.
Rusting Pipe are going through chemical changes
Heat is another factor that facilitates chemical reactions.
turning a piece of woodintoa bat
An example of a physical change occurs when making a baseball bat. Wood is carefully crafted into a shape which will allow a batter to best apply force on the ball. Even though the wood has changed shape and therefore physical properties, the chemical nature of the wood has not been altered. The bat and the original piece of wood are still the same chemical substance.
steam animation
water as steam or water vapor. It is formed when water is heated to the boiling point or it evaporates
ice animation
Ice is formed when water is cooled to the freezing point.
1. Which type of change occurs when the size, shape, appearance, or volume of a substance is changed without changing its composition? 2. With a physical change, is there a new substance formed?
3. can a chemical change be easily reversed? 4. whats the difference between chemical and physical change?
5. Which change can be easily be reversed? 6. When a new substance is formed with different properties than the original substance it is called a what? 7. If the chemical properties of a substance remain unchanged and the appearance or shape of an substance changes it is called a what? 8. Which is an example of a physical change? 19. What characteristic best describes what happen during a physical change?
By: Cheyenna Kemp
SCMS
vocabulary:
physical property- A characteristic that can be observed or measured without changing the identity of a substance.chemical property- a characteristic that determines how a substance will interact with other substances during a chemical reaction.
reactivity- how likely the atoms or molecules of one substance are to form bonds with the atoms or molecules of other substances.
physical change- alters the physical properties of a substance without changing the identity of a substance.
chemical change- occurs when one substance changes into a new substance with different properties.
chemical reaction-the process by witch new substances form during a chemical change.
precipitate- a solid formed by a chemical reaction that takes place in a solution
combustion reaction- a chemical reaction in which oxygen combines with certain other substances,and heat and light are given off.
Physical changes occur when objects undergo a change that does not change their chemical nature. A physical change involves a change in physical properties. Physical properties can be observed without changing the type of matter. Examples of physical properties include: texture, shape, size, color, odor, volume, mass, weight, and density
There are several differences between a physical and chemical change in matter or substances.
A physical change in a substance doesn't change what the substance is. In a chemical change where there is a chemical reaction, a new substance is formed and energy is either given off or absorbed.
For example, if a piece of paper is cut up into small pieces it still is paper. This would be a physical change in the shape and size of the paper. If the same piece of paper is burned, it is broken up into different substances that are not paper.
Physical changes can be reversed, chemical changes cannot be reversed with the substance changed back without extraordinary means, if at all. For example, a cup of water can be frozen when cooled and then can be returned to a liquid form when heated.
If one decided to mix sugar into water to make sugar water, this would be a physical change as the water could be left out to evaporate and the sugar crystals would remain. However, if one made a recipe for a cake with flour, water, sugar and other ingredients and baked them together, it would take extraordinary means to separate the various ingredients out to their original form.
When heat is given off in a chemical change or reaction, it is called an exothermic reaction. When heat is absorbed in a chemical change or reaction, it is called an endothermic reaction. The speed at which chemical reactions take place depend on the temperature pressure and how concentrated the substances involved in the chemical reaction are. Sometimes substances called catalysts are used to speed up or help along a chemical reaction. Light is helpful in the processing of film.
Chemical changes take place on the molecular level. A chemical change produces a new substance. Examples of chemical changes include combustion (burning), cooking an egg, rusting of an iron pan, and mixing hydrochloric acid and sodium hydroxide to make salt and water.
Heat is another factor that facilitates chemical reactions.
water as steam or water vapor. It is formed when water is heated to the boiling point or it evaporates
Ice is formed when water is cooled to the freezing point.
1. Which type of change occurs when the size, shape, appearance, or volume of a substance is changed without changing its composition?
2. With a physical change, is there a new substance formed?
3. can a chemical change be easily reversed?
4. whats the difference between chemical and physical change?
5. Which change can be easily be reversed?
6. When a new substance is formed with different properties than the original substance it is called a what?
7. If the chemical properties of a substance remain unchanged and the appearance or shape of an substance changes it is called a what?
8. Which is an example of a physical change?
19. What characteristic best describes what happen during a physical change?
Links:
http://en.wikipedia.org/wiki/Physical_change
http://en.wikipedia.org/wiki/Chemical_change
http://www.mcwdn.org/chemist/pcchange.html
http://chemistry.about.com/od/lecturenotesl3/a/chemphyschanges.htm
http://www.chem4kids.com/files/matter_chemphys.html
References:
Google
www.mcwdn.org
T Cap Coach
http://en.wikipedia.org/wiki/Physical_change